zit ships ReleaseFast, so --release names it. This reverses the ReleaseSafe pin; pack runs ~25x faster and read verbs are indistinguishable between the modes (ls over tcl's 300MB store is 0.31s fast against 0.33s safe, leaves 0.01s in both).

The cost is real: over a thousand std.debug.assert calls compile to nothing, so release_assert_test.zig stops being belt-and-braces and becomes the thing keeping an assert from standing in for validation of untrusted input. Its rationale is rewritten around that.

Stating a preference makes it the ONLY reachable release mode, which the old comment got wrong: it documented --release=fast as an escape hatch from the ReleaseSafe pin, and that flag produced a ReleaseSafe binary anyway -- safety strings present to prove it. Anything benchmarked through it before now measured the checked build. The ci pin moves from 'keeps assertions alive' to 'the mode is stated, not left to whoever packages', which is the part that survives the reversal. check-in: da904fbe1c user: dmestas tags: trunk